The National Security Agency allegedly siphoned Americans' communications without warrants from behind this door at an AT&T office in San Francisco.

Heads spun four years ago this weekend, when AT&T was accused of funneling every one of its customers’ electronic communications to the National Security Agency — without warrants.

A Jan. 31, 2006, lawsuit alleged major violations of the Fourth Amendment right to be free from warrantless searches and seizures. Such a sweeping breach seemed far-fetched.

Yet months after the lawsuit was lodged, the Electronic Frontier Foundation produced internal AT&T documents allegedly outlining secret rooms in AT&T offices connected to the NSA, which was siphoning all internet traffic, from e-mails to Voice Over Internet Protocol phone conversations.

But four years and a mountain of court briefs and rulings later, the legal system has never addressed the merits of the allegations — and likely never will. Even Congress has weighed in and passed legislation to prevent the allegations from being heard.

And many — including the former AT&T technician who produced the documents in the case and the EFF — believe the alleged dragnet surveillance program continues unabated today.

“Nothing has stopped the dragnet,” said Cindy Cohn, the EFF’s legal director, whose case had grown to include all of the nation’s leading internet service providers.

The Bush administration and now the Obama administration have neither admitted nor denied the allegations. Instead, they have declared the issue a state secret — one that would undermine the nation’s national security if exposed.

U.S. District Judge Vaughn Walker, the San Francisco judge presiding over the litigation, did not agree. The judge ruled two years ago the allegations against the nation’s telcos could proceed.

But a major obstacle stopped the case dead in its tracks, before the merits of the allegations could be litigated, and before the judge could consider ordering a halt to the alleged dragnet.

That roadblock was an act of Congress, one voted for by Sen. Barack Obama of Illinois and then signed by President George W. Bush in July 2008. The legislation handed the telcos retroactive immunity from being sued for participating in the alleged program. Judge Walker tossed the case.

Under the program, which The New York Times disclosed in December 2005, the NSA was eavesdropping on Americans’ telephone calls without warrants if the government believed the person on the other line was overseas and associated with terrorism.

Eyebrows were raised when the newspaper exposed the now-legalized program — a program considered by many as a breach of Americans’ privacy and an abuse of executive power.

In his defense, Bush said his war powers granted the presidency the authority to bypass Congress and undertake the Terror Surveillance Program.

The internal AT&T documents, however, suggest the TSP was just the tip of an eavesdropping iceberg.

That’s what Mark Klein believes. He’s the former AT&T technician who provided EFF with the documents — which were exposed by Wired.com while they were under court seal.

“They show an untargeted, massive vacuum cleaner sweeping up millions of peoples’ communications every second automatically,” Klein said in a telephone interview.

To be sure, Congress’ and the executive’s zeal to prevent litigation on the alleged surveillance dragnet was countered by the EFF and others. They then named the government, instead of the telcos, as the defendant.

It was ill-fated legal jockeying to skirt the immunity legislation.

The Obama administration claimed the government was immune from the latest litigation. Or if it wasn’t, the administration argued, the lawsuit could expose government secrets and should be barred. This despite Obama announcing he would limit the use of the state secrets privilege.

Again, the government and the courts declined to address the merits of the allegations.

This time, the same judge in the original EFF case sided with the government for reasons the government never claimed. Judge Walker likened the newest allegations to a “general grievance” from the public.

Walker ruled that the courts are not available to the public to mount such a challenge. The suits were barred, Walker ruled, because they seek “to employ judicial remedies to punish and bring to heel high-level government officials for the allegedly illegal and unconstitutional warrantless electronic-surveillance program or programs now widely, if incompletely, aired in the public forum.”

The EFF said it would appeal Walker’s latest decision. The appellate courts are also weighing whether Congress overstepped its boundaries when it killed the original allegations targeting the telecommunication companies.

That case, which tests presidential powers, is nearing its fourth year. It has bounced from an Oregon federal court to San Francisco federal court to the appellate courts and back — without ever addressing the allegations.

“The government,” said Jon Eisenberg, the plaintiffs’ lawyer in the case, “has been largely successful in evading a ruling on the merits of all these cases.”